Preheat oven to 180 degrees C. Grease and flour a 23cm x 23cm cake pan or line a muffin pan with paper liners.
In a medium bowl, cream together the sugar and butter. Beat in the eggs, one at a time, then stir in the vanilla essence.
Combine flour and baking powder, add to the creamed mixture and mix well. Finally stir in the milk until mixture is smooth. Pour or spoon into the prepared pan.
Bake in preheated oven for 30 to 40 minutes. For cupcakes, bake 20 to 25 minutes. Cake is done when it springs back to the touch.
Whipped Vanilla Bean Frosting
In a mixer whip butter for 8 minutes on medium speed. Butter will become very pale & creamy.
Add remaining ingredients and mix on low speed for 1 minute, then on medium speed for 6 minutes. Frosting will be very light, creamy, and fluffy.
You can swap the vanilla bean and use a total of 1 1/2 teaspoons of pure vanilla extract.